This invention generally relates to vehicle suspension systems. More particularly, this invention relates to an integrated axle adaptor and spring seat for vehicle suspension systems.
Commercial vehicle trailer axles typically include a simple beam axle that is effectively hung from the trailer chassis by leaf springs, for example, as part of a suspension arrangement to damp the vibration effects while the vehicle is in motion over a road surface. FIG. 5 schematically shows a conventional arrangement where a support portion 11 is associated with the trailer chassis. A conventional air spring 12 provides a means of suspension in a conventional manner. A suspension component 13 such as a support arm or leaf springs, depending on the particular vehicle, is secured at one end to the support 11 and associated with the air spring 12 as known. An axle 14 is secured in position relative to the suspension component 13 using a conventional spring seat 15 and plate 16. A pair of U-bolts 17 secure the axle, spring seat and plate in place on the suspension component 13. A separate axle adaptor 18 is secured to the axle 14 using a conventional welding technique.
The axle adaptor 18 provides a fixed base to which the brake torque associated with the operation of brake components can be transmitted. It is common to have a separate brake carrier secured to the axle adaptor and then to have braking components supported by the brake carrier. Assembling all of these components requires time and introduces additional space considerations and materials. Each of these presents drawbacks that ideally would be minimized.
Another drawback is that welding an axle adaptor to an axle has several complications and potential problems. One difficulty is that the welding process tends to distort the adaptor. Any distortion requires subsequent machining to ensure that the axle adaptor will appropriately support a brake carrier and other components. If the brake components cannot be squarely mounted to the adaptor and axle, for example, the system may not operate as desired.
Another drawback associated with welding the adaptor to the axle is that it introduces the possibility for weaknesses within the axle structure. It is known that axles are more likely to crack at weld locations because of the common change in the strength of the axle material adjacent to the weld. Appropriately placing the weld on an area of relatively low stress, near the neutral axis of the axle beam for example, tends to minimize the effects of such welds, but does not eliminate the issue.
Another approach has been to attempt to bolt the axle adaptor to the axle. A separate mounting flange on the axle is then required. Again, there are issues associated with securing the mounting flange to the axle. Additionally, a mounting flange introduces extra weight, cost and materials. Further, the fixing bolts required to attach the pieces together introduces further components and labor, reducing the economies of the assembly.
This invention addresses the need for economically and securely supporting brake components relative to an axle while avoiding the shortcomings and drawbacks of the prior art.
In general terms, this invention is a suspension assembly having an integrated axle adaptor and spring seat.
In one example assembly designed according to this invention, a seat member includes a first portion that is adapted to be at least partially received between the axle and a corresponding suspension component. A second portion of the seat member extends from the first portion and has at least one support surface that is adapted to support a brake component relative to the axle.
The seat member preferably comprises a single piece of metal so that the spring seat function and the adaptor function are performed by the same component. Having an integrally formed, single-piece component simplifies the assembly process, minimizes parts and labor and maximizes the economies of the assembly.
In one example, the second portion of the seat member is a combined axle adaptor and brake carrier so that it includes surfaces adapted to support the actual braking components and a separate brake carrier is not required. In one example, the seat member provides an inboard abutment surface for the brake components and an outboard abutment surface is selectively secured to the second portion of the seat member.
The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows.